The prior art discloses adjustable sockets for replacing the more conventional socket set which includes a number of different size sockets for driving bolts and nuts of different sizes. Usually such adjustable sockets are driven by either a ratchet wrench or a unitary wrench having a bent end that is received within a wrench opening. However, it is also possible to have adjustable sockets that are usable with straight wrenches having a handle end like a screwdriver or slidable wrench handles of the type normally used on hand taps.
Adjustable sockets conventionally include a plurality of jaws that are movable in a radial direction to receive and rotatively drive nuts and bolts of different sizes. The number of positions to which the jaws can be adjusted is usually great enough so that both English and metric size nuts and bolts can be driven by the socket upon appropriate adjustment. Thus, a mechanic can work on any particular job with an adjustable socket without having to constantly remove one socket from the wrench and replace it with another socket. The ever-constant search for a socket of a particular size is also eliminated by adjustable sockets.
The U.S. Pat. No. 2,582,444 of Lucht discloses an adjustable socket wherein movable jaws are mounted on a head of the socket for inward and outward movement under the control of a collar that is threaded to the head. Upon collar rotation in one direction, a spring moves the jaws outwardly to permit gripping of nuts or bolts of a larger size. Rotation of the collar in the other direction moves the jaws inwardly by a camming action against the bias of the spring. Thus, the operation of the socket involves the spring in both the opening and closing movements of the jaws.
Swedish Pat. No. 50357 of H. Warme, dated Sept. 28, 1918, discloses an adjustable wrench including two jaws which are movable on a rotatable driver in an angular relationship along the axis of rotation toward and away from each other by a worm type adjuster. Such a wrench is not adaptable to a three jaw construction such as is necessary to provide driving of conventional hexagonal nuts and bolts.
French Pat. No. 930,657 of M. Etienne Chol, dated July 18, 1947, discloses a three jaw adjustable wrench wherein a rotatable adjusting member has three pins each of which extends outwardly in a radial direction to a hole in the associated jaw to move the jaw axially and radially with respect to the rotational axis of the wrench. This type of wrench has not received any significant commercial acceptance, probably due to the fact that the pin and hole type of adjustment involved is not particularly well suited to manufacturing operations nor does such a construction provide an easily usable and effective socket with a length not substantially greater than normal single size sockets. Also, this type of adjustable socket can only be used when low torque application is involved.
The U.S. Pat. Nos. 4,213,355, 4,366,733, and 4,378,714 of Colvin disclose adjustable sockets wherein jaws are mounted on a driver by slideways for inward adjusting movement against a spring bias and for outward adjusting movement under the impetus of the spring bias. This adjusting movement is provided by rotation of an adjuster having a helical locking surface that engages a helical locking surface on the driver to move a sleeve that has camming surfaces engaged with camming surfaces of the jaws. While this type of adjustable socket has received significant commercial acceptance, both the inward and outward adjusting movement involve a spring bias like the Lucht U.S. Pat. No. 2,582,444 described above.
The U.S. Pat. Nos. 1,554,963, of Fisher, 2,850,931, Conway, and 2,884,826, Bruhn, disclose adjustable sockets that utilize pin and slot adjusters for providing adjustment of movable jaws between fully opened and closed positions. Such pin and slot connections require that a locking action be provided for controlling the position of the pin in the associated slot and necessarily increase the complexity of the socket.
Other adjustable sockets and the like are disclosed by U.S. Pat. Nos.: Johnson, 1,498,040; Secondi et al, 2,580,247; Clough, 2,669,896; Osborn, 2,701,489; Livermont, 3,102,732; and Nelson, 3,724,299.